1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <limits.h> 18 #include <errno.h> 19 #include <pthread.h> 20 #include <unistd.h> 21 #include <string.h> 22 #include <stdarg.h> 23 24 #include <sys/mman.h> 25 #include <sys/stat.h> 26 #include <sys/types.h> 27 #include <sys/ioctl.h> 28 29 #include <cutils/log.h> 30 #include <cutils/atomic.h> 31 32 #include <hardware/hardware.h> 33 #include <hardware/gralloc.h> 34 35 #include <linux/android_pmem.h> 36 37 #include "gralloc_priv.h" 38 39 40 // we need this for now because pmem cannot mmap at an offset 41 #define PMEM_HACK 1 42 43 /* desktop Linux needs a little help with gettid() */ 44 #if defined(ARCH_X86) && !defined(HAVE_ANDROID_OS) 45 #define __KERNEL__ 46 # include <linux/unistd.h> 47 pid_t gettid() { return syscall(__NR_gettid);} 48 #undef __KERNEL__ 49 #endif 50 51 /*****************************************************************************/ 52 53 static int gralloc_map(gralloc_module_t const* module, 54 buffer_handle_t handle, 55 void** vaddr) 56 { 57 private_handle_t* hnd = (private_handle_t*)handle; 58 if (!(hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER)) { 59 size_t size = hnd->size; 60 #if PMEM_HACK 61 size += hnd->offset; 62 #endif 63 void* mappedAddress = mmap(0, size, 64 PROT_READ|PROT_WRITE, MAP_SHARED, hnd->fd, 0); 65 if (mappedAddress == MAP_FAILED) { 66 ALOGE("Could not mmap handle %p, fd=%d (%s)", 67 handle, hnd->fd, strerror(errno)); 68 hnd->base = 0; 69 return -errno; 70 } 71 hnd->base = intptr_t(mappedAddress) + hnd->offset; 72 //ALOGD("gralloc_map() succeeded fd=%d, off=%d, size=%d, vaddr=%p", 73 // hnd->fd, hnd->offset, hnd->size, mappedAddress); 74 } 75 *vaddr = (void*)hnd->base; 76 return 0; 77 } 78 79 static int gralloc_unmap(gralloc_module_t const* module, 80 buffer_handle_t handle) 81 { 82 private_handle_t* hnd = (private_handle_t*)handle; 83 if (!(hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER)) { 84 void* base = (void*)hnd->base; 85 size_t size = hnd->size; 86 #if PMEM_HACK 87 base = (void*)(intptr_t(base) - hnd->offset); 88 size += hnd->offset; 89 #endif 90 //ALOGD("unmapping from %p, size=%d", base, size); 91 if (munmap(base, size) < 0) { 92 ALOGE("Could not unmap %s", strerror(errno)); 93 } 94 } 95 hnd->base = 0; 96 return 0; 97 } 98 99 /*****************************************************************************/ 100 101 static pthread_mutex_t sMapLock = PTHREAD_MUTEX_INITIALIZER; 102 103 /*****************************************************************************/ 104 105 int gralloc_register_buffer(gralloc_module_t const* module, 106 buffer_handle_t handle) 107 { 108 if (private_handle_t::validate(handle) < 0) 109 return -EINVAL; 110 111 // In this implementation, we don't need to do anything here 112 113 /* NOTE: we need to initialize the buffer as not mapped/not locked 114 * because it shouldn't when this function is called the first time 115 * in a new process. Ideally these flags shouldn't be part of the 116 * handle, but instead maintained in the kernel or at least 117 * out-of-line 118 */ 119 120 // if this handle was created in this process, then we keep it as is. 121 private_handle_t* hnd = (private_handle_t*)handle; 122 if (hnd->pid != getpid()) { 123 hnd->base = 0; 124 hnd->lockState = 0; 125 hnd->writeOwner = 0; 126 } 127 return 0; 128 } 129 130 int gralloc_unregister_buffer(gralloc_module_t const* module, 131 buffer_handle_t handle) 132 { 133 if (private_handle_t::validate(handle) < 0) 134 return -EINVAL; 135 136 /* 137 * If the buffer has been mapped during a lock operation, it's time 138 * to un-map it. It's an error to be here with a locked buffer. 139 * NOTE: the framebuffer is handled differently and is never unmapped. 140 */ 141 142 private_handle_t* hnd = (private_handle_t*)handle; 143 144 ALOGE_IF(hnd->lockState & private_handle_t::LOCK_STATE_READ_MASK, 145 "[unregister] handle %p still locked (state=%08x)", 146 hnd, hnd->lockState); 147 148 // never unmap buffers that were created in this process 149 if (hnd->pid != getpid()) { 150 if (hnd->lockState & private_handle_t::LOCK_STATE_MAPPED) { 151 gralloc_unmap(module, handle); 152 } 153 hnd->base = 0; 154 hnd->lockState = 0; 155 hnd->writeOwner = 0; 156 } 157 return 0; 158 } 159 160 int terminateBuffer(gralloc_module_t const* module, 161 private_handle_t* hnd) 162 { 163 /* 164 * If the buffer has been mapped during a lock operation, it's time 165 * to un-map it. It's an error to be here with a locked buffer. 166 */ 167 168 ALOGE_IF(hnd->lockState & private_handle_t::LOCK_STATE_READ_MASK, 169 "[terminate] handle %p still locked (state=%08x)", 170 hnd, hnd->lockState); 171 172 if (hnd->lockState & private_handle_t::LOCK_STATE_MAPPED) { 173 // this buffer was mapped, unmap it now 174 if ((hnd->flags & private_handle_t::PRIV_FLAGS_USES_PMEM) || 175 (hnd->flags & private_handle_t::PRIV_FLAGS_USES_PMEM_ADSP)) { 176 if (hnd->pid != getpid()) { 177 // ... unless it's a "master" pmem buffer, that is a buffer 178 // mapped in the process it's been allocated. 179 // (see gralloc_alloc_buffer()) 180 gralloc_unmap(module, hnd); 181 } 182 } else { 183 gralloc_unmap(module, hnd); 184 } 185 } 186 187 return 0; 188 } 189 190 int gralloc_lock(gralloc_module_t const* module, 191 buffer_handle_t handle, int usage, 192 int l, int t, int w, int h, 193 void** vaddr) 194 { 195 if (private_handle_t::validate(handle) < 0) 196 return -EINVAL; 197 198 int err = 0; 199 private_handle_t* hnd = (private_handle_t*)handle; 200 int32_t current_value, new_value; 201 int retry; 202 203 do { 204 current_value = hnd->lockState; 205 new_value = current_value; 206 207 if (current_value & private_handle_t::LOCK_STATE_WRITE) { 208 // already locked for write 209 ALOGE("handle %p already locked for write", handle); 210 return -EBUSY; 211 } else if (current_value & private_handle_t::LOCK_STATE_READ_MASK) { 212 // already locked for read 213 if (usage & (GRALLOC_USAGE_SW_WRITE_MASK | GRALLOC_USAGE_HW_RENDER)) { 214 ALOGE("handle %p already locked for read", handle); 215 return -EBUSY; 216 } else { 217 // this is not an error 218 //ALOGD("%p already locked for read... count = %d", 219 // handle, (current_value & ~(1<<31))); 220 } 221 } 222 223 // not currently locked 224 if (usage & (GRALLOC_USAGE_SW_WRITE_MASK | GRALLOC_USAGE_HW_RENDER)) { 225 // locking for write 226 new_value |= private_handle_t::LOCK_STATE_WRITE; 227 } 228 new_value++; 229 230 retry = android_atomic_cmpxchg(current_value, new_value, 231 (volatile int32_t*)&hnd->lockState); 232 } while (retry); 233 234 if (new_value & private_handle_t::LOCK_STATE_WRITE) { 235 // locking for write, store the tid 236 hnd->writeOwner = gettid(); 237 } 238 239 // if requesting sw write for non-framebuffer handles, flag for 240 // flushing at unlock 241 242 const uint32_t pmemMask = 243 private_handle_t::PRIV_FLAGS_USES_PMEM | 244 private_handle_t::PRIV_FLAGS_USES_PMEM_ADSP; 245 246 if ((usage & GRALLOC_USAGE_SW_WRITE_MASK) && 247 (hnd->flags & pmemMask) && 248 !(hnd->flags & private_handle_t::PRIV_FLAGS_FRAMEBUFFER)) { 249 hnd->flags |= private_handle_t::PRIV_FLAGS_NEEDS_FLUSH; 250 } 251 252 if (usage & (GRALLOC_USAGE_SW_READ_MASK | GRALLOC_USAGE_SW_WRITE_MASK)) { 253 if (!(current_value & private_handle_t::LOCK_STATE_MAPPED)) { 254 // we need to map for real 255 pthread_mutex_t* const lock = &sMapLock; 256 pthread_mutex_lock(lock); 257 if (!(hnd->lockState & private_handle_t::LOCK_STATE_MAPPED)) { 258 err = gralloc_map(module, handle, vaddr); 259 if (err == 0) { 260 android_atomic_or(private_handle_t::LOCK_STATE_MAPPED, 261 (volatile int32_t*)&(hnd->lockState)); 262 } 263 } 264 pthread_mutex_unlock(lock); 265 } 266 *vaddr = (void*)hnd->base; 267 } 268 269 return err; 270 } 271 272 int gralloc_unlock(gralloc_module_t const* module, 273 buffer_handle_t handle) 274 { 275 if (private_handle_t::validate(handle) < 0) 276 return -EINVAL; 277 278 private_handle_t* hnd = (private_handle_t*)handle; 279 int32_t current_value, new_value; 280 281 if (hnd->flags & private_handle_t::PRIV_FLAGS_NEEDS_FLUSH) { 282 struct pmem_region region; 283 int err; 284 285 region.offset = hnd->offset; 286 region.len = hnd->size; 287 err = ioctl(hnd->fd, PMEM_CACHE_FLUSH, ®ion); 288 ALOGE_IF(err < 0, "cannot flush handle %p (offs=%x len=%x)\n", 289 hnd, hnd->offset, hnd->size); 290 hnd->flags &= ~private_handle_t::PRIV_FLAGS_NEEDS_FLUSH; 291 } 292 293 do { 294 current_value = hnd->lockState; 295 new_value = current_value; 296 297 if (current_value & private_handle_t::LOCK_STATE_WRITE) { 298 // locked for write 299 if (hnd->writeOwner == gettid()) { 300 hnd->writeOwner = 0; 301 new_value &= ~private_handle_t::LOCK_STATE_WRITE; 302 } 303 } 304 305 if ((new_value & private_handle_t::LOCK_STATE_READ_MASK) == 0) { 306 ALOGE("handle %p not locked", handle); 307 return -EINVAL; 308 } 309 310 new_value--; 311 312 } while (android_atomic_cmpxchg(current_value, new_value, 313 (volatile int32_t*)&hnd->lockState)); 314 315 return 0; 316 } 317 318 /*****************************************************************************/ 319 320 int gralloc_perform(struct gralloc_module_t const* module, 321 int operation, ... ) 322 { 323 int res = -EINVAL; 324 return res; 325 } 326
